The Quilliams were completed
in 1942-1943 as the first of the War Emergency Destroyers or "Cubs". In
order to speed production, they were based as much as possible on
existing designs, having hulls very similar to the "J" class with a number of
changes in armament. The twin gun turrets were replaced with single gun
turrets and the torpedo armament was increased. One magazine was
converted to a fuel bunker to improve endurance.

The ships were designed to take three easily interchanged
sets of armament. Configuration 'A' is that shown above. Configuration
'B' was a maximum antisubmarine warfare configuration, which swapped one
4" gun for four additional depth charge throwers and a loadout of 120
depth charges. Configuration 'C' was a minesweeper version which also
sacrificed the fourth 4" gun and reduced the depth charge loadout to 45
depth charges in return for TSDS minesweeping gear.

Their completion was
delayed because of air raid damage to
the yards. A second group of identical design, the "R" class, had construction suspended because of the fall of France,
which prompted the Admiralty to suspend all construction that could not
be completed by the end of 1940 until the crisis had passed.
Construction resumed after the British victory in the Battle of Britain
reduced the threat of German invasion.

A number of units were manned by the Royal Australian
Navy, although they operated in the war against Germany until the
beginning of 1944 and remained under Royal Navy operational control
until the end of the war.